Blender jar

ABSTRACT

A blender jar defines a geometry to impart vertical movement to material being processed in the blender jar, and, alternatively or in combination, improves the horizontal movement to the blended material. By configuring one or more agitators on the floor of a jar, laminar flow or symmetric flow of material around the jar is disrupted. The material is forced in an upward direction in the jar and, therefore, into more frequent contact with the cutter blades rotating in the jar.

This application is a continuation of U.S. application Ser. No.11/052,338, now U.S. Pat. No. 7,350,963, filed Feb. 04, 2005, which isincorporated herein in its entirety.

The present invention relates to a blender jar construction adapted toimprove the blending performance of a blender. Specifically, the floorof the blender jar includes an agitator that imparts vertical movementto material that is being processed in the blender jar. Also, sidewallbumps are engineered relative to a blender blade path to improveperformance.

BACKGROUND OF THE INVENTION

Blender performance is the subject of considerable engineering byblender manufacturers. Efforts to improve blend consistency andefficiency have been directed to areas including blender cutter speed,blender cutter shape, and blender jar sidewall geometry. While each iseffective in improving performance in certain instances, these effortsalso have their limitations.

Blender cutter speed and speed variation has often been used to improveblending processes by speeding up or making variable the cutting andblending action of the cutter assembly. However, if the blades move toofast, then the rapid rotation may cause cavitation. If a user mustmanually vary the speed of operation of the blender, then such manualwork requires user attention during some or all of the blending process.

Blender cutter assemblies have also been engineered to help movematerial being processed as well as improve the processing of thematerial. The pitching of the blade may promote some vertical movementof material being processed. Angling of the blade will change the bladepath. If blade shape (including pitch and angle) is too aggressive,however, then the design may put extra strain on the blender motor. Ifthe blade shape is relatively flat, then it may be more prone tocavitation at high speeds of operation. In any event, the cutterassembly cannot alone be used to overcome dead zones that are created inthe material in a jar as a result of the processing inside a particularjar geometry.

Jar sidewall geometry has also been used to try to improve blenderperformance. In the early 1980's, for instance, a Nutone® blender(manufactured by Scovill) included a generally triangular-shaped jar.Two of the walls of the Nutone blender jar included bumps. The thirdwall had no bump. Further, the triangular cross-section of the blenderwas not symmetrical as the third wall was longer than the first twowalls. The cutter assembly was set closer to the third wall (no bump)than the other two walls. In operation, presumably as a result of theasymmetric sidewall geometry, the blender formed a vortex in thematerial being processed with the vortex centered away from the axisdefined by the shaft carrying the cutter. This movement of the vortex isexpected to help the efficiency of that blender.

Another recent attempt to improve blender operation through sidewallmodification is described in published United States Patent ApplicationNo. US2003/0213373 owned by K-Tec. As with the Nutone blender, thisblender manufactured by K-Tec claims to improve the performance of theblender by making the sidewalls asymmetrically configured around thecentral axis of the cutter assembly. In the K-Tec blender, a fifth wallis truncated so that it is closer to the blade path of the cutterassembly. As explained in that patent application, this geometry movesthe vortex of blended material in the blender away from the central axisand therefore improves performance of the blender.

As seen in both the Nutone and K-Tec blender jar configurations, themanipulation of sidewall geometry to an asymmetric configuration affectsthe horizontal flow of material within the blender jar. However, thesidewall geometry only primarily affects the horizontal flow ofmaterial. That is, the movement of material in the cross-sectionalplanes perpendicular to the vertical axis of the blender jar isaffected. Therefore, the sidewall geometry is limited to essentiallyaffecting only two dimensional change in material flow, i.e., in asingle plane.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to improve blenderjar geometry to promote three dimensional material flow. The jar wouldinclude a floor having an agitator. Alternatively, or in combinationwith an agitator, specific sidewall bumps may be used to improve thehorizontal flow of material within a blender jar.

In one example, a blender jar for promoting three dimensional materialflow comprises a floor and a sidewall connected to the floor andextending vertically upwardly from the floor to form a space inside thesidewall and above the floor where material is blended. The floorcomprises an opening through which extends a drive shaft. A cutterassembly is attached to the drive shaft, the cutter assembly comprisinga blade that rotates on the shaft inside the blender jar and above thefloor, the rotation of the blade defining a blade path. The floorcomprises an agitator that is closer to the blade path than theremainder of the floor, whereby material that is being processed in thejar has vertical motion imparted to it caused by contact with theagitator. The floor may comprise a plurality of agitators, and theagitators may be symmetrically spaced around the circumference of theopening in the floor. The agitators may be asymmetrically spaced aroundthe circumference of the opening in the floor. The sidewalls maycomprise a rib or a plurality of ribs. The sidewall may comprise a bumpor a plurality of bumps. The plurality of agitators may comprise aplurality of sizes.

In another example, a blender jar for promoting three dimensionalmaterial flow comprises a floor and a sidewall connected to the floorand extending vertically upwardly from the floor to form a space insidethe sidewall and above the floor where material is blended. The floorcomprises an opening through which extends a drive shaft. A cutterassembly is attached to the drive shaft, the cutter assembly comprisinga blade that rotates on the shaft inside the blender jar and above thefloor, the rotation of the blade defining a blade path. The sidewallcomprises a substantially circular cross section, and it furthercomprises a vertical bump therein. The size of the bump is defined asthe distance that surface of the bump is indented from the imaginarycircular radius of the sidewall. The minimum distance from the widestpoint of the blade path to the bump is about 25% to 55% of the size ofthe bump. In a further example, the minimum distance from the widestpoint of the blade path to the bump is about 30% to 45% of the size ofthe bump. The sidewall may further comprise a plurality of verticalbumps therein, and the plurality of vertical bumps may all have the samesize of bump. The floor may further comprise an agitator that is closerto the blade path than the remainder of the floor.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a blender jar in accordance with oneexample of the present invention.

FIG. 2 is a cut away, perspective view showing the floor of the blenderjar shown in FIG. 1.

FIG. 3 is a cross sectional, side elevation view of the jar shown inFIG. 1 taken along line 3-3 of FIG. 1.

FIG. 4 is a top plan view of the blender jar shown in FIG. 1 taken alongline of 4-4 of FIG. 1.

FIG. 5 is a perspective view of a blender jar in accordance with asecond example of the present invention.

FIG. 6 is a cut away, perspective view of the floor of the blender jarshown in FIG. 5.

FIGS. 7 a and 7 b are cross sectional, side elevation views of theblender jar shown in FIG. 5 taken along lines 7 a and 7 b perspectively.

FIG. 8 is a top plan view of the floor of the blender jar as shown inFIG. 5 taken along lines 8 of FIG. 5.

FIG. 9 is a perspective view of a third example of a blender jar inaccordance with the present invention.

FIG. 10 is a cut away view showing the bottom of the jar shown in FIG.1.

FIG. 11 is a side elevation cross sectional view of the blender jar asshown in FIG. 9 taken along line 11-11 of FIG. 9.

FIG. 12 is a top plan view of the blender jar as shown in FIG. 9 takenalong line 12-12 of FIG. 9.

FIG. 13 is a top plan view of the blender jar of FIG. 9 showing thecross-section of the jar in the same plane as the widest point of theblade tip path.

DETAILED DESCRIPTION

The present invention is directed to a modification of blender jargeometry to impart vertical movement to material being processed in theblender jar, and, alternatively or in combination, to improve horizontalmotion to the material. By configuring one or more agitators on thefloor of the jar, laminar flow or symmetric flow of material around thejar is disrupted. The material is forced in an upward direction in thejar and, therefore, into more frequent contact with the cutter bladesrotating in the jar.

A blender jar, in the most simple terms, includes a floor and a sidewallconnected to the floor. The sidewall extends upwardly from the floor toform a space inside the sidewall and above the floor where material maybe blended. The floor is the portion of the blender jar generally underthe plane that includes the blades of the cutter assembly when mountedin the jar and the path of those blades during operation. The floor maybe flat, angled, curved, or a combination thereof. The floor istypically described by “revolve” geometry that promotes a laminar flowof material in the circumferential direction. The floor includes anopening, typically in the center of the floor, through which a driveshaft extends. The cutter assembly is then mounted onto that driveshaft.

The sidewall of a jar may have a horizontal cross-sectional shape ofround, square, triangular, oval, or geometric shapes both symmetric orasymmetric or combinations thereof. The sidewall may include ribs thatare solid protrusions into the inside space of the jar. The sidewall mayfurther define vertical bumps, that are, in general terms, moresignificant in size than a rib. The bumps are inward protrusions ofvarious geometries. The bumps may be symmetric or asymmetricallyconfigured around the circumference of the jar. The ribs and bumps areused to impart turbulence with respect to the flow of material in thehorizontal planes that are the cross-sections of the blender jar andthat are parallel to the planes of the blade path defined by therotation of the cutter assembly. The bumps are further used to directthe flow of material back into the path of the blades to ensure that themix is recirculated through the blades for more complete blending. Thebottom of a sidewall interacts with or fits into a blender base duringoperation.

The blades in a blender jar make up the working component of the cutterassembly. The blades are connected to a shaft that is in turn connectedto a clutch. The shaft extends through the opening in the floor of thejar. The clutch is underneath the floor of the jar and mates with areciprocal clutch on the blender base to drive the rotation of thecutter assembly. In operation, the blade or blades rotate around in ahorizontal plane inside the jar. This rotation of blades defines a bladepath. The thickness of the blade path depends of the size, pitch andangling of the blades. For instance, if a flat blade is used, then thereis a relatively narrow blade path. Alternatively, if a highly pitchedblade is used, then a relatively wider blade path is defined.

The rotation of the blades of the cutter assembly inherently forcesmaterial in the horizontal, circumferential direction of the rotation ofthose blades. It must also be recognized that the pitch of the bladesmay also impart other directional forces on the material beingprocessed, but that flow is still primarily around the circumference ofthe inside of the jar.

An agitator is configured into the floor of a blender jar to takeadvantage of the circumferential flow of material caused by the blades.The agitator imparts a vertical direction component into the otherwisesubstantially laminar flow of material in the horizontal plane aroundthe circumference of the jar. An agitator is a raised surface in thefloor of a blender jar that disrupts or breaks laminar flow of materialin the circumferential direction. Stated conversely, the agitatorgeometry is contrary to a “revolve” geometry that promotes acircumferential, laminar flow of material. The agitator is a portion ofthe surface of the floor that is closer to the surface of the blade paththan the remainder of the floor. As such, the agitator will force theotherwise circumferential and laminar flow into an upward direction. Theresult is that the jar geometry promotes an upward vector of materialflow and gives better performance.

An agitator may be one surface or multiple different surfaces of ablender container floor. In other words, there may be two or moreagitators spaced around the circumference of the jar. In the case of twoor more agitators, they may be spaced symmetrically or asymmetricallyaround the circumference of the floor. The relative height of theagitator, in relation to the blade path, may be the same or differentwhen there are multiple agitators. The specific shape of an agitator maybe hemispheric, sinusoidal, planar, curved, or other geometricconfigurations and combinations thereof. These agitator geometries maybe generally parallel to the blade path plane. Alternatively, they maybe angled or curved to the plane of the blade path. The finalconfiguration of an agitator may be varied by the engineeringrequirements in specific cases based on the overall geometry of a givenjar.

The following examples are directed to alternative blender jargeometries that benefit from the addition of an agitator in therespective floors. Of course, other alternatives will be known to thoseof skill in the art given the benefit of the teachings herein.

EXAMPLE 1 FIGS. 1-4

FIGS. 1-4 illustrate a substantially four-sided blender jar 10. The jar10 has four sides 12 that make up the sidewall of the jar. The jar 10has rounded vertical corners 20 and vertical bumps 21 along the verticallength of the jar. The floor 14 of the jar 10 is generally smooth andprimarily embodies a revolve geometry to promote laminar flow in thecircumferential direction on the floor during operation. The jar 10includes a handle 16. The bottom portion 24 of the sidewalls 12 isadapted to be received in a blender base to secure the jar while theblender motor is operated to rotate a cutter assembly. The floor 14 alsoincludes a central opening or aperture 26 through which extends a driveshaft 35. The drive shaft 35 has a cutter assembly 36 mounted onto it.

The floor 14 also includes an agitator in the form of a horizontal hump30. The hump 30 is substantially the length of the radius of the jarfrom the central opening 26 to the sidewall 12. The height of the hump30, in one example, is about 0.170″ greater than the remaining portionof the floor 14 around the circumference of the opening 26. In otherwords, the top of the hump 30 is closer to the blade path defined by theblades 36 than the rest of the floor 14. As demonstrated specifically inFIG. 3, the length L1 from the top of the hump 30 to the bottom of theblade 36 is less than the length L2 from the top of the floor 14 to theblade 36. In this example, L1 is about 0.310″ and L2 is about 0.490″ forthe difference in distance of about 0.180°. The range of difference inthe distance between the top of an agitator to a blade path versus thedistance from a floor to a blade path can be about 0.100″ to 0.450″. Ofcourse, this range of difference may vary further depending on specificblender jar designs.

In testing, blender jars were compared for performance both with andwithout the agitator hump 30 on the floor 14 of the jar.

Testing was conducting by using the current Hamilton Beach Commercial“Tempest” 32 oz. container. One standard container (having revolvegeometry in its floor) had new blades installed into it and anothercontainer had these same blades installed along with an agitator in thefloor. The agitator had the single hump and geometry as shown in FIGS.1-4. The tests were run on similar 91650 base units set at 76% power(13,300 RPM) for a period of 12 seconds. A double Margarita mix was runin the unit. After blending, the mix was run through a sieve with holessized at 0.07″. The remaining mix was weighed on a scale. The testingresults are below:

Std. Container Container w/Agitator 6.512 5.136 7.6 6.134 6.14 5.4726.271 5.531 6.817 5.962 avg. 6.668 5.647From the data, it can be seen that more of the mix from the containerwith the agitator went through the sieve. This means that the particleswere broken down to a smaller size as a result of more efficientblending.

EXAMPLE 2 FIGS. 5-8

Another example of a blender jar is shown in FIGS. 5-8. The jar 50 has afundamentally round sidewall cross-section with two vertical bumps 53 onone side of the circular cross section. The floor 56 is curved insubstantial part in a revolve geometry. There is a handle 54. The bottomportion 58 of the sidewall 52 engages a blender base via the outsidegeometry of the jar (at the bumps) and a series of ribs and/or slots onthe base of the jar to hold the jar secure during operation.

The floor 56 includes multiple agitators, specifically, three surfaces57 and 59 that disrupt laminar flow around the jar 50 in thecircumferential direction. In this example, the pair of surfaces 57 aregenerally similar to each other. The surface 59 is similar in functionthe surfaces 57, but the surface 59 has slightly different geometry inthat it is configured between the two bumps 53 and the sidewall 52. Thesurfaces 57 and 59 are substantially flat planes that are closer to theblades 60 and the blade path formed by the rotation of the blades thanthe laminar, revolve geometry of the floor 56 generally. These surfaces57 and 59 create turbulence in the vertical direction of the flow ofmaterial that may be blended within the jar 50. In this example of a jar50, it can be seen that the agitator surfaces 57 and 59 in the floor 56work with the vertical bumps 53 in the sidewall of the jar to createturbulence in both the horizontal and vertical directions of flow ofmaterial within the jar.

In this example, the distance from surfaces 57 to the blade path isabout 0.13″, from surface 59 to the blade path is about 0.13″, and fromthe floor 56 to the blade path is about 0.36″.

In testing it was discovered that the jars with the floor agitators andsidewall bumps had superior performance results over a blender jarhaving a conventional, revolve geometry. Initial tests were conductedusing a container with a single bump added to the sidewall and acontainer from the current Hamilton Beach Commercial 908 blender thathas a mostly round cross section. This single bump unit included a bumphaving generally the same dimensions as either one of the bumps shown inFIGS. 5-8. The tests consisted of blending specified recipes anddetermining if the mix was blended completely in the prescribed amountof time (i.e. number of ice chunks) as well as measuring the yield andcalculating the deviation from the desired yield. On average, thecontainer with the single bump was determined to be superior to themostly round container in both categories as is indicated in the databelow for a single batch margarita.

Size Number of Ice Deviation of Ice Parti- Desired from Parti- clesYield Yield Yield Desired Trial Sample cles (in.) (mL) (oz.) (oz.) Yield(%) 1 Single 0 N/A 410 13.86 14.00 0.01 Bump 2 Single 0 N/A 400 13.5314.00 0.03 Bump 1 908 7 0.250 390 13.19 14.00 0.06 2 908 4 0.375 41013.86 14.00 0.01Further refinements to the design were then made and consisted of theaddition of a second bump at 120° to the initial bump as well as flooragitators spaced around the perimeter of the floor at 120° as shown inFIGS. 5-8. With the knowledge that the single bump was superior to themostly round container, a qualitative analysis was then conducted tocompare the container with the single bump to the refined design shownin FIGS. 5-8. The qualitative analysis consisted of blending batch sizesof 1, 2, and 3 drinks and having a random sampling of persons determinethe preferred drink profile. On the average, the refined design shown inFIGS. 5-8 was determined to be superior to the single bump design as isindicated by the following data for the margarita recipe.

Double Bump & Batch Size Agitators Single Bump 1 No Chunks - PreferredNo Chunks 2 No Chunks - Preferred No Chunks 3 No Chunks - Equal NoChunks

EXAMPLE 3 FIGS. 9-12

A still further example of a blender jar is shown in FIGS. 9-12. Likethe jar 50 shown in Example 2, jar 70 has a fundamentally round sidewallcross-section with two vertical bumps 73 on one side of the circularcross section. The floor 76 is curved in substantial part in a revolvedgeometry. There is a handle 74. The bottom portion 78 of the jar 70engages a blender base to hold the jar secure during operation.

The floor 76 includes multiple agitators, specifically, three surfaces77 and 79 that disrupt laminar flow around the jar 70 thecircumferential direction. In this example, the pair of surfaces 77 aregenerally similar to each other. The surface 79 is similar in functionto the surfaces 77, but the surface 59 has slightly different geometryin that it is configured between the two bumps 73 and the sidewalls 72.The surfaces 77 and 79 are substantially flat planes that are closer tothe blades 80 and the blade path formed by the rotation of the bladesthan the laminar, revolved geometry of the floor 76 generally. Thesesurfaces 77 and 79 create turbulence in the vertical direction of theflow of material that may be blended within the jar 70. In this exampleof the jar 70, it can be seen that the agitator surfaces 77 and 79 andthe floor 76 work with vertical bumps 73 in the sidewall of the jar tocreate turbulence in both the horizontal and vertical directions of flowof material within the jar.

In this example, the minimum distance from the surfaces 77 to thefarthest extending point of the blade path is about 0.505″ from surface79 to the blade path is about 0.497″, and from the floor 76 to the bladeis about 0.751″.

The primary differences between jar 50 (Example 2) and jar 70 (Example3) involve engineering variances suited for the particular blenderassemblies that would use the respective jars.

In testing it was discovered that the jars with the floor agitators hadsuperior performance results over a blender jar having a conventional,revolve geometry.

Testing—Protocol

A standard “small-batch” recipe consisting of 10 ice cubes (fromRubbermaid® square ice cube trays), 4 fluid ounces of pineapple juice, 3fluid ounces of coconut cream, and 1 fluid ounce of milk cream wasblended on the highest speed of the test unit for 30 seconds. After theallotted time, the mixture was poured through a #4 sieve ( 3/16″openings). The ice remaining in the jars was then weighed to achieve aquantitative analysis.

Testing—Results

The jar described herein in Example 3 and shown in FIGS. 9-12 was testedrelative to blender jars having a basic revolve shape using the sameblender motor and blade set. Over repeated tests, blending theaforementioned recipe, the revolve shape jars left “uncrushed ice” inthe sieve ranging from 40-90 grams. The jar described herein left“uncrushed ice” in the sieve ranging from 0-10 grams.

The test was repeated using a “large-batch” recipe that is equal toexactly three times the amount of all ingredients. The blending time washeld constant at 30 seconds. During repeated runs of this test, therevolved shape jars left “uncrushed ice” in the sieve ranging from20-100 grams. The jar described herein left “uncrushed ice” in the sieveranging from 0-4 grams.

Summary—The performance improvement gained with the jar geometrydescribed in FIG. 3 is quantitatively very substantial. This performanceenhancement also contributes to greatly improved blending efficiency.

EXAMPLE 4 FIG. 13

Jar 70 is the same as that shown in FIGS. 9-12, however thecross-sectional view is taken along the jar in the same plane as theblade tip path. FIG. 13 highlights the geometry of the sidewall bumps 73versus the widest point of the blade path 90. It has been found that thesize of the bumps, i.e. the distance d₁₀₅ that they are indented from animaginary circular radius 95, can improve blender efficiency. As shown,broken line 95 is the imaginary line of the blender jar sidewall if thecross section was substantially circular. The indented distance d₁₀₅,also referred to as the size of the bump, is the distance from theimaginary line 95 to the actual, bump inside surface 92. It has beendiscovered that the minimum distance d₁₀₀ from the widest point of theblade path 90 to the jar wall bump inside surface 92 should be about25-55% of the indented distance d₁₀₅. In a preferred embodiment, theminimum distance from the widest point of the blade path to the jar wallbump inside surface is about 30-45% of the indented distance.Engineering a jar outside these ranges of distance ratio is not asefficient as a jar having a construction in the cited ratios.

While the invention has been described with reference to specificembodiments thereof, it will be understood that numerous variations,modifications and additional embodiments are possible, and all suchvariations, modifications, and embodiments are to be regarded as beingwithin the spirit and scope of the invention.

1. A blender jar for promoting three dimensional material flow, the jarcomprising: a floor and a sidewall connected to the floor and extendingvertically upwardly from the floor to form a space inside the sidewalland above the floor where material is blended; the floor comprises anopening through which extends a drive shaft; a cutter assembly attachedto the drive shaft, the cutter assembly comprising a blade that rotateson the shaft inside the blender jar and above the floor, the rotation ofthe blade defining a blade path; wherein the sidewall comprises asubstantially circular cross-section; the sidewall further comprising avertical bump therein, wherein the size of the bump is defined as thedistance that the surface of the bump is indented from the imaginarycircular radius of the sidewall; wherein the minimum distance from thewidest point of the blade path to the bump is about 25% to 55% of thesize of the bump.
 2. A blender jar as described in claim 1, wherein theminimum distance from the widest point of the blade path to the bump isabout 30% to 45% of the size of the bump.
 3. A blender jar as describedin claim 1, wherein the sidewall further comprises a plurality ofvertical bumps therein.
 4. A blender jar as described in claim 3,wherein the plurality of vertical bumps are equally proportioned.
 5. Ablender jar as described in claim 4, wherein the sidewall comprises twobumps spaced about 120 degrees from each other around the circumferenceof the jar.
 6. A blender jar as described in claim 1, wherein the floorcomprises an agitator that is closer to the blade than the remainder ofthe floor.
 7. A blender jar as described in claim 6, further comprisinga first distance defined by the shortest possible line from the top ofthe agitator to the bottom of the blade; and a second distance definedby the shortest possible line from the top of the floor to the bottom ofthe blade, the second distance being 0.1 inches to 0.45 inches greaterthan the first distance.